The cause of allergies and other less well understood sensitivites lies within the body itself, in the inappropriate reaction of the immune system to the outside world, rather than external substances such as pollen. The immune system's array of defenses against truly harmful microorganisms turn against ordinarily harmless substances instead. The book looks at when antihistamines will help, and when they are a waste of money; why some allergens provoke instant, life-threatening reactions; why doctors distinguish between allergies and other kinds of sensitivities and intolerance; where clinical immunologists and clinical ecologists differ in their approach, and how you and your doctor can detect the causes of allergies. It shows the reader how to work out a healthy, balanced diet that avoids food allergy problems; how to tell if your children have allergies, and how to help them, and why, in the future, doctors will pay more attention to the psychological side of allergies.